Includes a merge of radiod and redirectord, updates to more modern Go
idioms, adoption of the higher level etcd concurrency primitives, and
a lot of other minor implementation changes.

The refactor is still incomplete: the daemons won't compile and the
code to start the RPC servers is missing.

Add an option to load a file containing redirects (source, target paths)
and serve them from the HTTP server, to allow renaming a radio without
breaking old links.

This change involves a refactoring of the DNS redirector code, which is
now a bit cleaner and has proper tests.

Split networking is where nodes communicate among themselves on a
private network (for example when behind a NAT infrastructure). This
change adds the --internal-ip option to radiod, that advertises a
separate IP for internal communication.

The only thing we need from ghost is the GZIPHandler. The
gorilla/handlers package has a CompressHandler, and much fewer
dependencies. Also, add a test that attempts a request with
an Accept-Encoding: deflate header.

RemoteAddr again.

Also removed some unnecessary duplication of code from net/http.

Proxied connections to Icecast are now handled with a simple TCP
proxy that can shutdown each direction independently. Fixes some
connection leaks.

Adds detailed information about the transcoding hierarchy and parameters.

Refactor the HTTP handler hierarchy to make it simpler.

Replace the ghost logging handler with a simpler one, that fires as soon
as the HTTP request headers are sent (this is a better solution for
long-lived connections).

Add a debug page to track long-lived HTTP request.

Add tests for the HTTP server.

Adds optional transcoding parameters to a Mount. Each node will then
start a master election for every transcoded stream, and the master will
run liquidsoap to re-encode the data. Transcoding mounts are identical
in other respects to normal mounts, except that liquidsoap acts as a
source for them.

Refactor the load balancing code using a generic traffic control
abstraction that gives the user more control over the final logic (for
the moment this is configured via a command-line parameter).

Introduce node names, allowing a node to have multiple IP addresses.
Also, make the front-end code IPv6-aware and support AAAA records.

This allows running the service on a single port: with the
--enable-icecast-proxy option, all requests can go through
redirectord.